• Molecules and Cells
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• v.25 no.3
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• pp.438-445
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• 2008

Leaf senescence is a highly regulated genetic process that constitutes the last stage of plant development and provides adaptive fitness by relocating metabolites from senescing leaves to reproducing seeds. Characterization of various senescence mutants, mostly in Arabidopsis, and genome-wide analyses of gene expression, have identified a wide array of regulatory components, including transcription factors and enzymes as well as signaling molecules mediating growth hormones and environmental stress responses. In this work we demonstrate that a membrane-associated NAC transcription factor, NTL9, mediates osmotic stress signaling in leaf senescence. The NTL9 gene is induced by osmotic stress. Furthermore, activation of the dormant, membrane-associated NTL9 is elevated under the same conditions. A series of senescence-associated genes (SAGs) were upregulated in transgenic plants overexpressing an activated form of NTL9, and some of them were slightly but reproducibly downregulated in a T-DNA insertional NTL9 knockout mutant. These observations indicate that NTL9 mediates osmotic stress responses that affect leaf senescence, providing a genetic link between intrinsic genetic programs and external signals in the control of leaf senescence.

• The Korean Journal of Ecology
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• v.24 no.4
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• pp.223-226
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• 2001

The leaf water relations and photosynthetic rate during acute soil drying were compared in potgrown grapevine cultivars, Vitis vinifera cv. Chardonnay and V. vinifera cv. Riesling. Leaf water potential in Riesling decreased significantly from day 2 after water had been withheld, while in Chardonnay leaf water potential for the water-stressed plants was almost identical with that in well watered plants during the first 4 days. Higher stomatal conductance and photosynthetic rate in Chardonnay than Riesling were observed until day 3 after withholding water. Photosynthetic rate in water-stressed Chardonnay was not different from that in control plants until day 3 after withholding water, while that in water-stressed Riesling was reduced markedly from day 2. In Riesling, osmotic potential at turgor loss point was not changed irrespective of watering conditions. However, in Chardonnay osmotic potential at turgor loss point decreased more in the water stressed conditions than in well watered conditions. The osmotic adjustment in Chardonnay under water stress conditions must contribute to the maintenance of higher stomatal conductance and photosynthetic rate than those in Riesling for a significant period of the drying process. Though difference in stomatal conductance between the two cultivars was shown in the process of soil drying, stomatal conductance of both cultivars responded to vapor pressure difference between leaf and ambient air, rather than soil water status and leaf water potential.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.1
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• pp.139-148
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• 2000

The osmotic pressure is a one of the most important factor affecting stabilization of multiple emulsion in a law hours after experiment. To understand and decrease osmotic pressure between Wl phase and W2 phase, a kinds of humectants were introduced in outer water phase. As a result, Betaine and Glucose had an excellent effect reducing osmotic pressure and NaCl made W/O/W emulsion more stable than MgSO4 did when introduced in inner water phase.

• BMB Reports
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• v.40 no.6
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• pp.1083-1089
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• 2007

The HAP complex has been found in many eukaryotic organisms. HAP recognizes the CCAAT box present in the promoters of 30% of all eukaryotic genes. The HAP complex consists of three subunits - HAP2, HAP3 and HAP5. In this paper, we report the biological function of the AtHAP3b gene that encodes one of the HAP3 subunits in Arabidopsis. Compared with wild-type plants, hap3b-1 and hap3b-2 mutants exhibited a delayed flowering time under long-day photoperiod conditions. Moreover, the transcription levels of FT were substantially lower in the mutants than in the wild-type plants. These results imply that AtHAP3b may function in the control of flowering time by regulating the expression of FT in Arabidopsis. In a subsequent study, AtHAP3b was found to be induced by osmotic stress. Under osmotic stress conditions, the hap3b- 1 and hap3b-2 mutants flowered considerably later than the wild-type plants. These results suggest that the AtHAP3b gene plays more important roles in the control of flowering under osmotic stress in Arabidopsis.

• The Journal of the Korean Society for Microbiology
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• v.22 no.2
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• pp.109-116
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• 1987

As a process to establish an effective preventive measure of V. vulnificus septicemia, bactericidal effect of distilled water against V. vulnificus was studied. When about $2.0{\times}10^7\;CFU/ml$ of V. vulnificus was inoculated in distilled water, a dramatic decrease in the number of viable bacteria by 5 to $6LOG_{10}$ was observed in 5 minutes. Bactericidal kinetic curves could be divided into the first rapid killing phase until 1 minute and the later slow killing phase after then, showing the heterogeneity of the bacterial population inoculated. When V. vulnificus was inoculated in saline solutions having various salinities, significant decrease in the number of viable bacteria was noted only at salinities under 0.2%. The higher was the concentration of NaCl, the greater was the degree of protection against osmotic shock. When glucose, NaCl, $MgCl_2$, and $CaCl_2$ were diluted with deionized water to give same osmolarities and V. vulnificus was inoculated in each of them to compare the bactericidal curves plotted during the first 5 minutes after inoculation, the protection efficiencies were in the order of $MgCl_2>CaCl_2{\gg}NaCl{\gg}glucose$. Above results indicate that treatment(or thorough washing) of contaminated sea animals or other products with distilled water can be used as a preventive measure of V. vulnificus septicemia, and divalent cations can protect V. vulnifcus to osmotic shock with high efficiency.

• Journal of Korean Neurosurgical Society
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• v.38 no.6
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• pp.431-434
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• 2005

Objective : Subarachnoid hemorrhage[SAH] is commonly associated with polyuria [solute diuresis or water diuresis]. The authors investigate the incidence and clinical characteristics of polyuria with special reference to the administration of osmotic diuretics. Methods : One hundred and forty eight patients with high urine output [>200ml/hr] after ruptured cerebral aneurysm operated early from Jan 1998 to Jun 2003 were selected. Water diuresis [diabetes insipidus, DI] was differentiated from solute diuresis by lower urine specific gravity [<1.005] and higher plasma osmolality. The incidence and mode of onset of polyuria were compared between two types of diuresis. Additionally, the relationships between development of polyuria and clinical features including aneurysm location, clinical grade, Fisher grade, and outcome were analyzed. Osmotic diuretics were not routinely used in patients with Hunt-Hess grade I-III since July 2001. Results : Annual incidence of polyuria decreased markedly since July 2001 : 45.2% in 1998, 34.5% in 2001, 11.9% in 2003. Postoperative DI occurred in $2.4{\sim}11.1%$. DI developed mainly from ruptured anterior communicating artery aneurysm. The mean interval between the last SAH and the onset of DI was 7.1 days [range $1{\sim}27$ days] and lasted mean 4.6 days. When compared with solute diuresis, the development of DI was significantly delayed. Other clinical features were not closely related to polyuria. Conclusion : Uncontrolled polyuria may lead to cerebral ischemia and electrolyte imbalance because SAH patients are already predisposed to hypovolemia, and will risk precipitating the opposite situation with overhydration. We can decrease the development of polyuria without routine use of osmotic diuretics, by avoiding the increased intracranial pressure such as the intraoperative ventriculostomy and gentle brain retraction in good grade patients.

• The Korean Journal of Food And Nutrition
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• v.35 no.6
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• pp.426-434
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• 2022

In this study, the effect of osmotic drying conditions of mangoes on hot air drying was investigated. Four different osmotic agents of 60 Brix, such as S60, SM10, HF80, and SG25, were prepared. Mango slabs were osmotically dried with the agents at a ratio of 1:4 (w/w) for up to 8 hours. SG25 showed the lowest weight reduction and moisture loss during the process. As a result of hot-air drying, all samples showed a high correlation with the Page model (0.9761~0.9997), and the required drying time of all samples that were osmotically dried was reduced compared to the non-osmotically dried group. After hot-air drying, the pH value increased according to the drying temperature. The L, a, and b values and the total polyphenol content also decreased. Through this study, the possibility of osmotic drying was confirmed to increase the efficiency of hot air drying of mangoes, which is expected to contribute to the industrial use of domestic mangoes.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.2137-2139
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• 2004

Cancer cell lysis at pulsed DC is realized using micromachined electrodes. In this research, quantitative analyses are performed on cell lysis results. The cell volume increasing at the pulses applied are analyzed in different medium conditions on osmotic pressure and conductivity, and the cell lysis procedures are studied in detail experimentally. Phosphate buffered saline (PBS) is used as the medium. To change the conductivity of PBS, NaCl concentration of PBS is adjusted, and inositol is used with PBS to control the effects of the osmotic pressure to cell lysis performance.

• Macromolecular Research
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• v.17 no.10
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• pp.763-769
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• 2009

A chromatographic method is used to measure interactions between dissimilar proteins in aqueous electrolyte solutions as a function of ionic strength, salt type, and pH. One protein is immobilized on the surface of the stationary phase, and the other is dissolved in electrolyte solution conditions flowing over that surface. The relative retention of proteins reflects the mean interactions between immobile and mobile proteins. The osmotic cross second virial coefficient calculated by assuming a proposed potential function shows that the interactions of unfavorable proteins depend on solution conditions, and the proposed model shows good agreement with the experimental data of the given systems.

• Journal of the Korean Society of Visualization
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• v.4 no.1
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• pp.31-40
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• 2006

In this study a newly designed electro-osmotic micro-mixer is proposed. This study is composed of a channel and metal electrodes attached locally on the side wall surface ultimately to control the mixing effect. To obtain the flow patterns, numerical computation was performed by using a commercial code, CFD-ACE. The fluid-flow solutions are the cast into studying the characteristics of stirring in terms of the mixing index. It was shown that the local control of the electric potential can indeed contribute to the enhancement of mixing effect.